Shamusworld >> Repos - rmac/blob - object.c

   1 //
   2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
   3 // OBJECT.C - Writing Object Files
   4 // Copyright (C) 199x Landon Dyer, 2011 Reboot and Friends
   5 // RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
   6 // Source utilised with the kind permission of Landon Dyer
   7 //
   8
   9 #include "object.h"
  10 #include "sect.h"
  11 #include "symbol.h"
  12 #include "mark.h"
  13 #include "error.h"
  14 #include "riscasm.h"
  15 #include "mark.h"
  16
  17 /*
  18  *  Imports
  19  */
  20 extern int obj_format;          // object file format to write
  21 extern int prg_flag;            // generate Atari ST direct executable
  22
  23 LONG symsize = 0;                       // Size of BSD symbol table
  24 LONG strindx = 0x00000004;      // BSD string table index
  25 char * strtable;                        // Pointer to the symbol string table
  26 char * objImage;                        // Global object image pointer
  27
  28
  29 //
  30 // Add an entry to the BSD symbol table
  31 //
  32 char * constr_bsdsymtab(char * buf, SYM * sym, int globflag)
  33 {
  34         chptr = buf;                                            // Point to buffer for deposit longs
  35         D_long(strindx);                                        // Deposit the symbol string index
  36
  37         WORD w1 = sym->sattr;                           // Obtain symbol attribute
  38         int w2 = sym->sattre;
  39         LONG z = 0;                                                     // Initialise resulting symbol flags
  40
  41         if (w1 & EQUATED)
  42         {
  43                 z = 0x02000000;                                 // Set equated flag
  44         }
  45         else
  46         {
  47                 switch (w1 & TDB)
  48                 {
  49                 case TEXT: z = 0x04000000; break;       // Set TEXT segment flag
  50                 case DATA: z = 0x06000000; break;       // Set DATA segment flag
  51                 case BSS : z = 0x08000000; break;       // Set BSS segment flag
  52                 }
  53         }
  54
  55         if (globflag)
  56                 z |= 0x01000000;                                // Set global flag if requested
  57
  58         D_long(z);                                                      // Deposit symbol attribute
  59
  60         z = sym->svalue;                                        // Obtain symbol value
  61         w1 &= DATA | BSS;                                       // Determine DATA or BSS flag
  62
  63         if (w1)
  64                 z += sect[TEXT].sloc;                   // If DATA or BSS add TEXT segment size
  65
  66         if (w1 & BSS)
  67                 z += sect[DATA].sloc;                   // If BSS add DATA segment size
  68
  69         D_long(z);                                                      // Deposit symbol value
  70
  71         strcpy(strtable + strindx, sym->sname);
  72
  73         strindx += strlen(sym->sname) + 1;      // Incr string index incl null terminate
  74         buf += 12;                                                      // Increment buffer to next record
  75         symsize += 12;                                          // Increment symbol table size
  76
  77         return buf;
  78 }
  79
  80
  81 /*
  82  *  Alcyon symbol flags
  83  */
  84 #define AL_DEFINED      0x8000
  85 #define AL_EQUATED      0x4000
  86 #define AL_GLOBAL       0x2000
  87 #define AL_EQUREG       0x1000
  88 #define AL_EXTERN       0x0800
  89 #define AL_DATA         0x0400
  90 #define AL_TEXT         0x0200
  91 #define AL_BSS          0x0100
  92 #define AL_FILE         0x0080
  93
  94 LONG PRGFLAGS;          /* PRGFLAGS as defined in Atari Compendium Chapter 2 */
  95                                         /* Definition   Bit(s)  Meaning */
  96                                         /* PF_FASTLOAD  0               If set, clear only the BSS area on program load,              */
  97                                         /*                                              otherwise clear the entire heap.                              */
  98                                         /* PF_TTRAMLOAD 1               If set, the program may be loaded into alternative RAM,       */
  99                                         /*                                              otherwise it must be loaded into standard RAM.                */
 100                                         /* PF_TTRAMMEM  2               If set, the program's Malloc() requests may be satisfied      */
 101                                         /*                                              from alternative RAM, otherwise they must be satisfied        */
 102                                         /*                                              from standard RAM.                                            */
 103                                         /* -                    3               Currently unused.                                             */
 104                                         /* See left.    4 & 5   If these bits are set to 0 (PF_PRIVATE), the processes'       */
 105                                         /*                                              entire memory space will be considered private                */
 106                                         /*                                              (when memory protection is enabled).If these bits are         */
 107                                         /*                                              set to 1 (PF_GLOBAL), the processes' entire memory space      */
 108                                         /*                                              will be readable and writable by any process (i.e. global).   */
 109                                         /*                                              If these bits are set to 2 (PF_SUPERVISOR), the processes'    */
 110                                         /*                                              entire memory space will only be readable and writable by     */
 111                                         /*                                              itself and any other process in supervisor mode.If these      */
 112                                         /*                                              bits are set to 3 (PF_READABLE), the processes' entire memory */
 113                                         /*                                              space will be readable by any application but only            */
 114                                         /*                                              writable by itself.                                           */
 115                                         /* -                    6-15    Currently unused.                                             */
 116
 117 static WORD tdb_tab[] = {
 118         0,                              /* absolute */
 119         AL_TEXT,                /* TEXT segment based */
 120         AL_DATA, 0,             /* DATA segment based */
 121         AL_BSS                  /* BSS segment based */
 122 };
 123
 124
 125 #define HDRSIZE 0x1C            /* size of Alcyon header */
 126
 127
 128 /*
 129  *  Add entry to symbol table;
 130  *  if `globflag' is 1, make the symbol global;
 131  *  if in .PRG mode, adjust symbol values for fake link.
 132  *
 133  */
 134 char * constr_symtab(register char * buf, SYM * sym, int globflag)
 135 {
 136         register int i;
 137         register char * s;
 138         register WORD w;
 139         register LONG z;
 140         register WORD w1;
 141
 142         /*
 143          *  Copy symbol name
 144          */
 145         s = sym->sname;
 146
 147         for(i=0; i<8 && *s; i++)
 148                 *buf++ = *s++;
 149
 150         while (i++ < 8)
 151                 *buf++ = '\0';
 152
 153         /*
 154          *  Construct and deposit flag word
 155          *
 156          *      o  all symbols are AL_DEFINED
 157          *      o  install T/D/B/A base
 158          *    o  install 'equated'
 159          *    o  commons (COMMON) are AL_EXTERN, but not BSS
 160          *      o  exports (DEFINED) are AL_GLOBAL
 161          *      o  imports (~DEFINED) are AL_EXTERN
 162          *
 163          */
 164         w1 = sym->sattr;
 165         w = AL_DEFINED | tdb_tab[w1 & TDB];
 166
 167         if (w1 & EQUATED)               /* equated */
 168                 w |= AL_EQUATED;
 169
 170         if (w1 & COMMON)
 171         {
 172                 w |= AL_EXTERN | AL_GLOBAL;     /* common symbol */
 173                 w &= ~AL_BSS;           /* they're not BSS in Alcyon object files */
 174         }
 175         else if (w1 & DEFINED)
 176         {
 177                 if (globflag)           /* export the symbol */
 178                         w |= AL_GLOBAL;
 179         }
 180         else w |= AL_EXTERN;            /* imported symbol */
 181
 182         *buf++ = w >> 8;
 183         *buf++ = (char)w;
 184
 185         z = sym->svalue;
 186
 187         if (prg_flag)                   /* relocate value in .PRG segment */
 188         {
 189                 w1 &= DATA | BSS;
 190
 191                 if (w1)
 192                         z += sect[TEXT].sloc;
 193
 194                 if (w1 & BSS)
 195                         z += sect[DATA].sloc;
 196         }
 197
 198         *buf++ = z >> 24;               /* deposit symbol value */
 199         *buf++ = z >> 16;
 200         *buf++ = z >> 8;
 201         *buf++ = z;
 202
 203         return buf;
 204 }
 205
 206
 207 //
 208 // Write an object file to the passed in file descriptor
 209 // N.B.: Return value is ignored...
 210 //
 211 int WriteObject(int fd)
 212 {
 213         LONG t;                                 // Scratch long
 214         LONG tds;                               // TEXT & DATA segment size
 215         int i;                                  // Temporary int
 216         CHUNK * cp;                             // Chunk (for gather)
 217         char * buf;                             // Scratch area
 218         char * p;                               // Temporary ptr
 219         LONG ssize;                             // Size of symbols
 220         LONG trsize, drsize;    // Size of relocations
 221         long unused;                    // For supressing 'write' warnings
 222
 223         if (verb_flag)
 224         {
 225                 printf("TEXT segment: %d bytes\n", sect[TEXT].sloc);
 226                 printf("DATA segment: %d bytes\n", sect[DATA].sloc);
 227                 printf("BSS  segment: %d bytes\n", sect[BSS].sloc);
 228         }
 229
 230         // Write requested object file...
 231         switch (obj_format)
 232         {
 233         case BSD:
 234                 if (verb_flag)
 235                 {
 236                         printf("Total       : %d bytes\n", sect[TEXT].sloc + sect[DATA].sloc + sect[BSS].sloc);
 237                 }
 238                 ssize = ((LONG)sy_assign(NULL, NULL));          // Assign index numbers to the symbols
 239                 tds = sect[TEXT].sloc + sect[DATA].sloc;        // Get size of TEXT and DATA segment
 240                 buf = malloc(0x600000);                                         // Allocate 6mb object file image memory
 241
 242                 if (buf == NULL)
 243                 {
 244                         error("cannot allocate object file memory (in BSD mode)");
 245                         return ERROR;
 246                 }
 247
 248                 memset(buf, 0, 0x600000);               // Reset allocated memory
 249                 objImage = buf;                                 // Set global object image pointer
 250                 strtable = malloc(0x200000);    // Allocate 2mb scratch buffer
 251
 252                 if (strtable == NULL)
 253                 {
 254                         error("cannot allocate string table memory (in BSD mode)");
 255                         return ERROR;
 256                 }
 257
 258                 memset(strtable, 0, 0x200000);  // Reset allocated memory
 259
 260                 // Build object file header
 261                 chptr = buf;                                    // Base of header
 262                 D_long(0x00000107);                             // Magic number
 263                 D_long(sect[TEXT].sloc);                // TEXT size
 264                 D_long(sect[DATA].sloc);                // DATA size
 265                 D_long(sect[BSS].sloc);                 // BSS size
 266                 D_long(0x00000000);                             // Symbol size
 267                 D_long(0x00000000);                             // First entry (0L)
 268                 D_long(0x00000000);                             // TEXT relocation size
 269                 D_long(0x00000000);                             // BSD relocation size
 270
 271                 // Construct TEXT and DATA segments (without relocation changes)
 272                 p = buf + BSDHDRSIZE;
 273
 274                 for(i=TEXT; i<=DATA; ++i)
 275                 {
 276                         for(cp=sect[i].sfcode; cp!=NULL; cp=cp->chnext)
 277                         {
 278                                 memcpy(p, cp->chptr, cp->ch_size);
 279                                 p += cp->ch_size;
 280                         }
 281                 }
 282
 283                 // Do relocation tables (and make changes to segment data)
 284                 p = buf + (BSDHDRSIZE + tds);   // Move obj image ptr to reloc info
 285                 trsize = bsdmarkimg(p, tds, sect[TEXT].sloc, TEXT);// Do TEXT relocation table
 286                 chptr = buf + 24;                               // Point to relocation hdr entry
 287                 D_long(trsize);                                 // Write the relocation table size
 288                 p = buf + (BSDHDRSIZE + tds + trsize);  // Move obj image ptr to reloc info
 289                 drsize = bsdmarkimg(p, tds, sect[TEXT].sloc, DATA);// Do DATA relocation table
 290                 chptr = buf + 28;                               // Point to relocation hdr entry
 291                 D_long(drsize);                                 // Write the relocation table size
 292
 293                 p = buf + (BSDHDRSIZE + tds + trsize + drsize);// Point to start of symbol table
 294                 sy_assign(p, constr_bsdsymtab); // Build symbol and string tables
 295                 chptr = buf + 16;                               // Point to sym table size hdr entry
 296                 D_long(symsize);                                // Write the symbol table size
 297
 298                 // Point to string table
 299                 p = buf + (BSDHDRSIZE + tds + trsize + drsize + symsize);
 300
 301                 memcpy(p, strtable, strindx);   // Copy string table to object image
 302
 303                 if (buf)
 304                         free(strtable);                         // Free allocated memory
 305
 306                 chptr = p;                                              // Point to string table size long
 307                 D_long(strindx);                                // Write string table size
 308
 309                 // Write the BSD object file from the object image buffer
 310                 unused = write(fd, buf, BSDHDRSIZE + tds + trsize + drsize + symsize + strindx + 4);
 311
 312                 if (buf)
 313                         free(buf);                                      // Free allocated memory
 314
 315                 break;
 316
 317         case ALCYON:
 318                 if (verb_flag)
 319                 {
 320                         if (prg_flag)
 321                         {
 322                                 printf("TOS header  : 28 bytes\n");
 323                                 printf("Total       : %d bytes\n", 28 + sect[TEXT].sloc + sect[DATA].sloc + sect[BSS].sloc);
 324                         }
 325                         else
 326                         {
 327                                 printf("Total       : %d bytes\n", sect[TEXT].sloc + sect[DATA].sloc + sect[BSS].sloc);
 328                         }
 329                 }
 330                 /*
 331                  *  Compute size of symbol table;
 332                  *   assign numbers to the symbols...
 333                  */
 334                 ssize = 0;
 335
 336                 if (prg_flag != 1)
 337                         ssize = ((LONG)sy_assign(NULL, NULL)) * 14;
 338
 339                 /*
 340                  *  Alloc memory for header+text+data, symbol and
 341                  *   relocation information construction.
 342                  */
 343                 t = tds = sect[TEXT].sloc + sect[DATA].sloc;
 344
 345                 if (t < ssize)
 346                         t = ssize;
 347
 348                 buf = (char *)((int)malloc(t + HDRSIZE) + HDRSIZE);
 349
 350                 /*
 351                  *  Build object file header
 352                  *   just before the text+data image
 353                  */
 354                 chptr = buf - HDRSIZE;  /* -> base of header */
 355                 D_word(0x601a);                 /* 00 - magic number */
 356                 t = sect[TEXT].sloc;    /* 02 - TEXT size */
 357                 D_long(t);
 358                 t = sect[DATA].sloc;    /* 06 - DATA size */
 359                 D_long(t);
 360                 t = sect[BSS].sloc;             /* 0a - BSS size */
 361                 D_long(t);
 362                 D_long(ssize);                  /* 0e - symbol table size */
 363                 D_long(0);                              /* 12 - stack size (unused) */
 364                 D_long(PRGFLAGS);               /* 16 - PRGFLAGS */
 365                 D_word(0);                              /* 1a - relocation information exists */
 366
 367                 /*
 368                  *  Construct text and data segments;
 369                  *  fixup relocatable longs in .PRG mode;
 370                  *  finally write the header+text+data
 371                  */
 372                 p = buf;
 373
 374                 for(i=TEXT; i<=DATA; i++)
 375                 {
 376                         for (cp=sect[i].sfcode; cp!=NULL; cp=cp->chnext)
 377                         {
 378                                 memcpy(p, cp->chptr, cp->ch_size);
 379                                 p += cp->ch_size;
 380                         }
 381                 }
 382
 383                 if (prg_flag)
 384                         markimg(buf, tds, sect[TEXT].sloc, 0);
 385
 386                 write(fd, buf - HDRSIZE, tds + HDRSIZE);
 387
 388                 /*
 389                  *  Construct and write symbol table
 390                  */
 391                 if (prg_flag != 1)
 392                 {
 393                         sy_assign(buf, constr_symtab);
 394                         write(fd, buf, ssize);
 395                 }
 396
 397                 /*
 398                  *  Construct and write relocation information;
 399                  *   the size of it changes if we're writing a RELMODed executable.
 400                  */
 401                 tds = markimg(buf, tds, sect[TEXT].sloc, 1);
 402                 write(fd, buf, tds);
 403                 break;
 404         }
 405
 406         return 0;
 407 }
 408